Liquid feed carburetor



March 14, 1944. G. GERSON I LIQUID FEED CARBURE'IORI Filed Aug. 8. 1941 INVENTOR GERHARD GERSON BY Patented Mar. 14, 1944 amuse LIQUID FEED csnnnnnroa Gerhard Gerson, Kecgo Harbor,

Mich, assignor to Phillips Petroleum Company, a corporation of Delaware Application August 8, 1941, Serial No. 406,064

1 Claim.

This invention relates to a carburetor for internal combustion engines, and more particularly, it relates to a carburetor for utilizing fuels having a. wide boiling range.

The present invention has for its purpo e t provide a carbureting arrangement which is adapted to deliver high pressure fuels such as natural gasoline and butane to the intake manifold in liquid phase without the occurrence ofv vaporization or vapor lock in the lines and connections between the fuel tank an th carburetor Jet. The carburetion of fuels of this type presents a peculiar problem since they contain constituents which are either entirely gaseous at ordinary temperatures and pressures as in the case of butane, or exist simultaneously in the liquid and gaseous phase as in the case of natural gasolines. Fuels of the latter type ordinarily consist of a mixture of heavy and relatively light hydrocarbons, the light fractions coneisting mainly of mixtures of propane and butane and'arestored in tanks under their own vapor pressure. the light fractions remaining in solution with the heavier fractions under the existing superatmospheric pressure.

Due to the high volatility of fuels of the aforementioned type, carburetors of conventional design are eminently unsuitable as means for getting the fuel from the tank to the engine in the proper proportions. Vaporization will occur immediately as the pressure on the fuel is reduced. The fuels are particularly desirable for internal combustion engines due to their exceptionally high anti-knock value and it has been the practice to utilize gas carburetors for their carburetion which completely vaporize the fuel after it leaves the tank. These arrangements are par,

ticularly bulky and expensive while the present invention provides an arrangement whereby the fuel is eiilciently and accurately carbureted in the liquid phase without the occurrence of vapor lock.

My invention has for its primary object the I provision of a carburetor apparatus for utilising volatile compounds having a wide boiling range as motor fuel for internal combustion engines.

Another obiect of this invention is to provide a carburetor ior utilizing a variety of fuels including natural gasolines, butane, and the like.

A still further object is to provide a carburetor which will operate with fuels of varying vapor pressures without requiring a manual change of adjustments.

These and additional objects and advantages of this invention will be apparent to those skilled. in the art by reference to the following description and annexed drawing which pertains to preferred embodiment of my invention; wherein the figure is an elevation view of my invention. partly in cross section.

Referring to the figure I have denoted therein a carburetor barrel or gas-air mixing tube by reference numeral Ill. in barrel i0 above a throttle valve l2, and is provided with a plurality of openings it which communicate with a passag H. Throttle valve 12 is mounted on a shaft I! which extends through the barrel and is connected to a means (not shown) which regulates the valve's opening and closing in a manner common to the art.

A conduit l 6 connects with passage I4 and with a chamber Ii which is formed in a diaphram housing connected to the lower portion of barrel l0. The chamber II is formed in the diaphragm housing between the outer portion thereof and a diaphragm plate 52 which is contained within the housing. The chamber]! communicates with openings i3 of the venturi ii through conduit It and passage H. A valve stem 53 is positioned within the housing and is secured to the diaphragm plate Stem It extends through the central portion of housing Ill and barrel I! and is free to move upon movement ofplate 82. A needle valve 24, which is secured to stem 2:, regulates the opening and closing of a fuel induction orifice 25 which is provided-inn preferably non-metallic discharge end flora-conduit 21. is formed of a synthetic plastic to prevent premature vaporization in the tube duYC' to manifold heat.

This conduit communicates with the interior of a shut-oil valve casing 28 which contains a master valve for shutting oil flow oi fluid from the tank to the outlet orifice when the motor has stopped.

A compression spring ll of any desired strength is contained in housing 50 and in a hollow extension 55 of the housing. The spring is positioned between the outer face of diaphragm plate I! and-a collar I! fixed in extension 55. An air bleed valve ll, which is closed when needle valve 24 is closed, is formed on the outer end of stem '3 and extension 55 to assist in controlling the opening and closing of the needle valve. The air bleed valve influences the suction eflect on the diaphragm to compensate for pressure fluctuations below the main throttle valve. A lever 58 which ispivotallymounted onextension 88 is connected at the top to stem 53 and at the bottom to a cable 88 which is connected at the other end to a pivotally mounted eccentric element I.

twill s venturi II is positioned be noted fromv the drawing that a roller merit of lever the drawing that a,

valve M, while the other end is Si i employed to give e. desired direction of the movement of lever 53, however, is to be understood that any suitable type of linkages, cables, and the like which will produce the desired move- 58 may be used satisfactorily. Elemerit to is pivotelly otteched to a stem '82 which in. turn is secured to e diaphragm plate which is contained within 9. diaphragm housing 6 5. A compression spring $5 of an desired strength is positionedebout stem 62 between the diaphragm housing and plate E3. Spring 55 is adjusted to maintain piste E3 in e, predetermined position against the pressure of the fuel which acts on the opuosite side of the plate from spring so through a. branch conduit fill which communicates with the right hand po ion of the diaphragm housing and with fuel conduit 5. It will be noted in stem tl is used to open shutofi valve 28 when the internal combustion engine, for which this carburetor is adopted, is storted up. Stem 8? is urged downwardly e lever which is controlled and operated item a remote source in e, well-known leaner.

An. oil chamber is formed in the lower hortion o! the valve casing 28 which communicates with the lubricating system of an internal combustion engine (not shown) through c conduit 3%. It will be noted. from the drawing that e passage is This passage comrmmlcates with conduit ill and with the interiors? l9. wl'lere the passage connects with the barrel it is restricted by on ediustment screw ill. ofl velve M is provided in the passage 3% to control the opening Shut-oil valve 5} is operated from throttle valve shaft is through the medium oi e pivoted lever by means of a. linkage Q2 shown in dotted. lines. One end of the lever i3 beers on the end of the shut ofi yleldingly connected with linkage It will he further noted that when the internal combustion engine is idling or at very low loeds, velve ll ls open and fuel enters barrel it through passage 3%. At other locals oi? the engine when throttle 62 is open, velve ll will be completely closed.

In the operation or the device it will be noted that the fuel induced into the intake manifold does not begin to vaporize normally until it has been inducted into mixing tube ill. When the internal combustion engine is operating, master velve is regulated by the pressure of the oil in the lubricsting system in the manner The amount of fuel which is inducted into cerhuretor barrel it through conduit ill, orifice 25, and needle valve fi l ls controlledby the suction crested from the psssege of sir M. The needle valve is also controlled to comnensote 101' changes in the vepor pressure of the tool. The pressure of the fuel in conduit it sets upon diaphragm of diaphragm hour. lug through conduit G8, urging plate 53 to the left egcinst the action of spring 65. As stem is secured to plate it also moves to the left, cousing element fill to rotate in e clockwise direction. Upon the rotation oi element 51%, cable moves lower portion of lever Ell to the left which he turn pivots the upper portion of level.- to the right. As the upper end of lever ls uttccheu to vel've stein the stem moves to the right with the uction the suction. csused by the passage o veoturi it. This tends to close le vslve and. restrict or. lcunt of fuel leaving orifice 2E, chewing the proper proportion of fuel and stir to outer irltslze monii'old. Ely employing my up through venturl of spring and against peratus, I am able to maintain the volume of fuel entering barrel "l at a desired amount regardless of an increase in vapor pressure. On the other hand, should the vap r pressure of the loci decrease to below the no operating range, my device would operate to allow needle valve M to open a greater amount. In the use of high pressure fuels, vaporization does not occur in the the fuel is subjected to the vapor pressure of the fuel at the source of fuel supply.

possible regardless of chenge in supply pressure due to variation in the temperature of the fuel.

- It will he co erent that the amount of fuel enterdescribed.

illl

iunctloh oi the area. 0! the user pressure of the fuel. u open, air is admitted through eir bleed valve Ell into chamber 5! to reduce the 19121 suction acting on diaphragm 3Tb cohscquently to reduce the movement 91, diaphragm end of needle valve 2 3 during the operation oi the internal combustioh engine. Valve realises possible a smooth change of needle velve movement throughout the range of speeds for all leads, which facilitates the proportionlng oi the amounts of fuel and air induced to the intake manifold. in starting the internal combustion engine, stem cl is urged downwardly Toy lever t8, opening master valve 28, and thus allowing fuel in conduit 34' to enter conduit El. As throttle plate 12 is closed, valve M is open, and fuel flows into barrel l0 through passage 39, and thence to the intake manifold.

From the foregoing, it is believed that the operation and advantages of the apparatus for practicing my instant invention will be readily comprehended by persons skilled in the art. It is to be clearly understood, however, that various changes in the apparatus shown and described may be resorted to without departing from the spirit of the invention, as defined by the appended cleim.

I claim:

In a cerburetion system for internal combustion engines adopted for handling liquid fuel of relatively high vapor pressure including a. mixins tube having a venturi. a throttle valve in the mixing tube, a. fuel supply, an outlet orifice for delivering liquid fuel into the mixing tube, below the throttle valve, means for maintaining said fuel in liquid phase from the fuel supply to the outlet orifice comprising a fuel valve for said orifice, a diaphragm housing, a diaphragm in said housing operably connected with the fuel valve and forming a. chamber on one side communicating barrel is c. orifice opening and the when needle vsive oppositeside being in communication with the atmosphere, spring means urging said fuel valve closed, so that suction induced by air flow through the venturi conmlunlcated to the diaphragm will open the fuel valve against the action or said spring means. an air bleed valve in said chamber connected with the fuel valve for influencing the suction efiect communicated to the diaphragm from the venturi, to compensate for pressure fluctuation on the fuel outlet below the throttle valve, pressure responsive means communicating with the fuel supply upstream or the outlet orifice, spring nieams acting: on said pressure responsive means in opposition to fuel pressure, and means operstoiy connecting the pressure responsive means with. the fuel valve to vary the degree 0! loading: on said fuel valve in accordance with variation in pressure in the fuel supply.

GERHARD GEESON. 

